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    MCU/MPU/DSP > Development Platforms & Kits > Daughter / Add-on boards >
    GertBOT Robotics Add-on Board for Raspberry Pi

    Overview

    GERTBOT offers a simple entry in to robotics with Raspberry Pi. While full robotics capability, like motor feedback, is not available on GERTBOT, its price point makes it an attractive and useful plug and play introduction to robotic controls. GERTBOT works with Raspberry Pi Model A, B and B.

    The Gertbot is a motor/power controller board for the Raspberry-Pi. The strength of the board is that it has its own CPU which frees up the Raspberry-Pi from a lot of intense computations and will take care of all the real time requirements. All you have to do is give it high level commands. Like: Board 2, Motor 1, take 2432 steps at 67 Hz. Even giving those commands is done for you using the free GUI which comes with it!

    Specific Applications: Walking Robot, Robotic Arms, Balancing Robots

    Features

    Hardware features:

    • Four H-bridges 8V-30V, 2.5A
    • Bridges can be re-configured for 2x 5A or 1x 10A
    • Two open drain outputs 30V, 3A
    • Power full 64MHZ ARM Cortex-M3 processor
    • RS232 connects direct to the Raspberry-Pi or other serial interface
    • Cascade port to control up to four boards at a time
    • 20-pin connector programmable for:
      • Automatic motor end-stop
      • Four 12-Bit ADC ports
      • Two 12-bit DAC ports
      • 8-16 general purpose I/O

    Software controllable features:

    • Brushed motors:
      • Control direction
      • Speed control PWM 10Hz-10KHz, 0-100%
      • Soft start 0.1sec .. 5 seconds prevents in-rush current
      • Stop on switch hit
    • Stepper motors:
      • Take X-steps in either direction
      • Step speed 0.06 Hz .. 5KHz
      • Stop on switch hit
    • Digital Command Control (model train control):
      • Can send any DCC command 3..6 bytes
      • Programmable pre-amble length and repeat count
    • Short-circuit or high temperature error detection
    • On error, keep running, stop motor, stop board or stop all boards
    • I/O pins programmable functions
    • Emergency stop, halts whole system

    Ships With

    • GERTBOT Add-on Board

    FAQs

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    What can be controlled by the Gertbot?
    A single Gertbot can handle 4 dc brushed motors, 2 stepper motors, or anything requiring 8 to 30 volts and up to 10A (2.5A per channel). It can even generate Digital Command Control signals (or DCC) from all 4 channels for model railroad applications.
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    Can the Gertbot be connected to an RS232 port?
    The Gertbot can't be connected directly to RS232 as the voltage allowed on RS232 will damage the board. You will need to use an adapter or voltage level converter.
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    How do I connect multiple boards to my Raspberry Pi?
    You will need to make a "Cascade cable" using an 8 position ribbon cable with up to 4 connectors. The length of the cable will depend on how much space you allow between the boards. Only the first board will connect to the Raspberry Pi. The other boards will connect via your cascade cable. Please see the Advanced guide for full details.
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    Can the the 4 control channels be reconfigured to operate in parallel?
    Yes, the Gertbot can be reconfigured to have 2 channels operating in parallel or all 4 channels in parallel . Reconfiguring will require desoldering and moving some of the control resistors. The procedure to do this would differ depending upon your application. Please see the advanced guide for full details and instructions.
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    Can I use a debugger and then re-program the Gertbot for my own purposes?
    A debugger will not work with the Gertbot right out of the box, but you can re-program the board for your own application. To do this you will need to perform a "board erase" to wipe the existing program off of the Gertbot. After that is complete, you can use an Atmel JTAG debugger to re-program the board.
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    What other features does the Gertbot have?
    20 pin header with: 4 x 12-bit ADC ports, 2 x 12-bit DAC ports, & 8 to 18 general purpose I/O ports. 2 x N type open drain MOSFET outputs rated for 30V 3A. A 64MHz ARM Cortex-M3 controller. The board can also be programed to shut down or keep going if one motor fails. The I/O ports can also be connected to switches or voltage-free contact sensors to operate as end stops or serve as an E-stop function.

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